Automatic stoker



Dec. 25, 1934. J E |MR|E ET AL 1,985,660

AUTOMATIC STOKER Filed April 22, 1931 3 Sheets-Sheet l v V mm Q W (Ittor m6:

Dec. 25; 1934. J, E, IMRIE ET AL AUTOMAT I C STOKER Filed April 22, 1931 3 Sheets-Sheet 2 Enventor-S w 4%, Jamsl'. [mr a 1w Patented Dec. 25, 1934 UNITED ,STATES PATENT OFFICE AUTOMATIC STOKER J ames E. 'Imrie and William Walter Hudson,

Salt Lake City, Utah of the fire throughthe sev eral openings provided at that purpose in thefirepotcr tuyere block within thefurnac'e. r r

This difii'culty isin great part due to the prevalentcustom of connecting the air-supply pipe from the "fan toga point at one side or-the other of the tuyere block instead of centrally as is usually the case with the coal-supply pipe. This arrarlg-lamentnaturally tends to cause most of the air supplied to pass through the openings or tuyeres on that side of the tuyere block at which itis introduced from the air-supply pipe,and to "fstarve those {on thecpposite side; thus causing an *over-supply of air to'one side of the'fire andinadequatesupply to the other side. This results in seriously interfering with the efficient operationof the furnace,

An object and purpose "of the invention is to arrange for the introduction of the air to the tuyere block in such a manner as to overcome the foregoing difiiculties and to facilitate the symmetrical distribution of the air to both sides of the fire.

A further object of the invention is to provide a device in which the air is introduced in such manner that it willrhave a cooling efiect upon the conveyor, coal-supply pipe and coal content of same, thus preventing over-heating taking place and avoiding possible damage to the screw driven by the electric or other motor 16 through conveyor and the coal-supply pipe.

Additional objects of the invention areto provide a blower and air-pipe assembly that will be unusually neat and compact, and to so locate the blower, etc., that the air-pipe to the tuyere block will be as short and straight as possible.

With the foregoingand other objects in view, the invention will be more fully described hereinafter, and will be more particularly pointed out in the claims appended hereto.

In the drawings, wherein like symbols refer to the same or corresponding parts throughout the several views:

Figure 1 is a side elevation, with parts broken away and parts shown in section, of an improved furnace and automatic stoker constructed in accordance with the present invention.

Figure 2 is a horizontal section taken on the line 2-2 in Figure 1 with parts broken away,

Application April 22,- 1931, Serial No. 532,054 'iolaim. (01.11045 Figure 3 is a fragmentary plan view, on an enlarged scale of the tuyere block and pipe con-, nections.

Figure 4 is a vertical longitudinal section taken on the line 4-4 in Figure 3. 5

Figure 5 is a horizontal'longitudinal section taken on the line 5--5 in Figure'4. Figure 6 is a horizontal section line 66 in Figure 4.

Figure 7 is a similar view taken on the line 7-7 in Figure 4, and 7 7 t Figure 8 is a cross section taken on the line taken on the 8-'8 also in Figure 4.

Referring more particularly to the drawings 10 designates a hot-air furnaceconstructed in any conventional manner. The hot air furnace has been selected for illustration as being the most. convenient type to show on the drawings, but the invention is, of course, equally applicable to other types of furnaces, such as steam and hot water, and those for special industrial applications.

With the furnace 10 is associated an automatic stoker consisting of the coal hopper .11, coalsupply pipe 12 and air-supplypipe 1'3 connecting with the base member 14 of theretort structure comprising said member and an annular tuyere block 19 mounted thereon. The base member 14 includes an inner fuel passage or compartment 21 communicating with fuel pipe 12, and an outer a suitable mechanical train 17. Air is forced through pipe 13 to tuyere block 14 by a fan or blower is, which may be driven by the same mo- 40 tor 16.

The air-supply pipe 13 is in the form of a jacket completely enclosing the coal-supply pipe 12 along substantially its entire length from the point where it leaves the coal hopper 11 to the point where it enters the base member 14. It will be evident that the two pipes 12 and 13 enter the base member 14 at such point and in such a direction that the coal entering the inner compartment 21 of the base member and the air entering the air jacket 22, are in each case evenly and symmetrically distributed; the coal being evenly spread and propelled up through the inner compartment 21; and the air propelled with equal iorce and in equal volume around through both sides of air jacket 22 so that there is no tendency for either coal or air to accumulate more at any one point than at any other. The coal, therefore, forms a symmetrical pile or bed in the inner compartment 21 and flows evenly over all sides of the same into the body of the fire in the furnace as indicated in Figure l. The air passes up and around through the air jacket 22 and enters the fuel bed symmetrically from all directions through apertures or tuyeres 23.

It will also be seen from the drawings that the air-supply pipe 13, on account of its shape and location surrounding the coal supply pipe 12 provides a continuous flow of air from the fan or blower 18, in the form of an annular blanket surrounding pipe 12 for substantially its. entire length, thus causing a cooling effect on coalsupply pipe 12 and screw conveyor 15, and preventing them from becoming over-heatedwith undesirable and possibly dangerous results.

- It will also be seen that the location of the fan 18 renders possible the use of an unusually short air-supply pipe 13 and one free from an excessive number of bends, this pipe being unvaryingly straight from the point of introduction of the air from the. fan 18 to the point where the pipe enters the base member 14. There is also compactness and, general desirability about'the arrangement shown.

It will thus bevevident that all of the purposes of the invention are fulfilled, namely: the invention provides means for the even and symmetrical distribution of the combustion airin the improved tuyere block; it also provides a cooling film of air 5 surrounding the coal-supply pipe 12, thus preventing the over-heating of the same and of the screw conveyor and coal. being conveyed; and it provides a short, straight air-supply pipe 13 from the fan to the tuyere block, together with a, generally neat and compact arrangement of the device as a whole.

In Figure 8 the two parts of the retort structure are shown as connected together by lugs 24 and bolts or other fastenings'25; although the i securing of these parts together might be accomplished in any manner where it is desirable to manufacture the same separately.

The upper portion of the base member 14 is, of course, open upwardly not only as regards the inner chamber 21 but also with respect to the air jacket 22. Connecting Webs 26 may be arranged between the outer walls of the jacket 22 and the Walls of the inner coal chamber 21. The pipes 12 and 13 may be connected with the base member in any appropriate manner. a

In Figure 5 we have shown the air-pipe 13 asfitting within a flange 27 of the base member and against a shoulder 28 thereof; While the inner coal-supply pipe 12 is disposed within an inner flange 29 and against a shoulder 30 of the base member, the pipe being held in place by bolts 31 which screw into the base member and engage lugs 32 of the pipe 12.

It is obvious that various changes and modifications' may be made in the details of constructionand design of the abovespecifically described embodiment of this invention without departing from the spirit thereof, such changes and modifications being restricted only by the scope of the following claim.

What is claimed is: 7

In an automatic stoker for furnaces, a'retort structure comprising a base member and tuyere block disposed in the furnace, said base member and said block each having an inner fuel compartment and an outer air jacket surrounding the same, said air jacket and fuel compartment of the'base member being provided with cylindric coaxial intake flanges, a fuel pipe having its end inserted in the intake flange of the fuel compartment, outstanding lugs carried by said fuel pipe, spacing members engaging the fuel compartment and the air jacket of the base member, securing means engaging said lugs and said spacing members for. detachably securing said fuel pipe to the base member, and an air pipe having its end inserted in the flange of the air jacket.

JAMES E. IMRIE.

WILLIAM WALTER HUDSON. 

